1. Centre d'Ingénierie des Protéines, Université de Liège, Belgium
2. Centre d'Ingénierie des Protéines, Université de Liège, Belgium and Department of Microbiology, Toho University, School of Medicine, Japan
3. Department of Microbiology, Toho University, School of Medicine, Japan
4. Dipartimento di Biologia Molecolare, Sezione di Microbiologia, Università di Siena, Siena, Italy
5. Laboratory of Microbiology, Ospedale di Circolo e Fondazione Macchi, Varese, Italy
6. Department S.T.B., Università dell'Aquila, Aquila, Italy